THERESA May has ordered EU leaders to stop Russia's "horrific" actions in Syria amid fears some countries are dragging their feet.

The Prime Minister told her European counterparts that they must act and wants the EU to send a "robust united message" to Moscow over its bombing campaign supporting Syrian dictator Bashar al-Assad.

During tonight’s EU summit, Mrs May told EU leaders that the current assault on Aleppo is "particularly horrific" and Russia's actions have "undermined the West's efforts" to provide a political settlement, according to No 10 sources.

They said Mrs May is warning leaders they "must be ready to take steps to change Russia's approach and the way it thinks about this if we are ever to bring an end to the violence in Syria".

GETTY/ REUTERS

Theresa May has urged EU leaders to stop Vladimir Putin's involvement in Syria

Aleppo under siege

A fighter from the Syrian pro-government forces mans a riffle inside a damaged house in the recently recaptured village of Joubah during an offensive towards the area of Al-Bab in Aleppo province, on November 25, 2016.

Russia’s only aircraft carrier alongside an arsenal of heavily armed ships including a battlecruiser and two destroyers are currently lurking just outside British waters as they make they way to Syria.

The fleet is expected to move through the English Channel, past Gibraltar and into the Mediterranean Sea to the Syrian coast.